<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="zh-CN">

<head>
<title>用css来控制</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="description" content="html 12小时入门" />
<style>
	div{
	width:300px;
	height:200px;
	background-color:blue;
	}
	
	#header{
	background:blue;
	}
	
	
	
</style>
</head>

<body>
	<div id="header">	</div>
	<div id="main">	</div>
	<div id="footer">	</div>
</body>
</html>
